I've happened across a PDF facsimile (one file per NT book) of Benjamin Wilson's Emphatic Diaglott, published originally in 1864. It is an interlinear Greek New Testament.

Normally I wouldn't note this, but — if I understand the title correctly — this is the only online source I know of representing Griesbach's edition of the Greek New Testament.

Here's the full title:

The Emphatic Diaglott: Containing the Original Greek Text of what is commonly styled the New Testament, (According to the Recension of Dr. J.J. Griesbach,) with an Interlineary Word for Word English Translation; A New Emphatic Version, Based on the Interlineary Translation, on the Renderings of Eminent Critics, and on the Various Readings of The Vatican Manuscript, No. 1209 in the Vatican Library. Together with Illustrative and Explanatory Foot Notes, and a Copious Selection of References, to the whole of which is added, A Valuable Alphabetical Appendix.

Phew. That's a title. So the Greek text on the page is Griesbach's, but the Greek text of the running translation in the outside margin is based on Wilson's own textual work? Seems weird to not have the two aligned to the same vorlage. Anyway, here's a capture of a portion representing 1Ti 2.3-6:

If you're interested in downloading it, you can do that from here.